1. Field of the Invention
The invention concerns a multiple extrusion nozzle for extruding and/or filling hand held and convenience snack food products having two or more axial cavities comprising potato shreds and methods of making a multiple tube-shaped snack food. The multiple extrusion nozzle comprises an outer extrusion segment and an inner extrusion segment which can be inserted into the outer extrusion segment. The inner extrusion segment comprises two or more channels. Dough, preferably dough comprising potato shreds is extruded through an annular space defined by the walls of the outer extrusion segment and inner extrusion segment and filling is extruded, injected, stuffed or otherwise placed into axial cavities through the inner extrusion segment.
2. The Related Art
Hand held convenience snack foods having a filling surrounded by a casing typically have casings made from bakery formulas involving pastry dough. Bakery formulas generally involve grains and flours and the pastry dough tends to be homogenous which is both easy to form by extrusion or other means, or otherwise easy to fill. An example is cereal bar mixes made with pastry dough comprising multi-grains, and although these materials tend to have coarser grains compared to other pastry dough ingredients, the particles have substantial uniformity thus facilitating extrusion and filling.
Potato shreds are nonuniform and have bigger and longer particle size compared to grains and flours. As a result, dough comprising potato shreds lacks uniformity and is more difficult to handle and extrude. Dough comprising potato shreds will have the tendency to form open surfaces after extrusion or during the forming or filling process.
U.S. Pat. No. 4,888,192 concerns a method of extruding baked goods in the form of an extruded rope comprised of three materials. An outer expanded crispy layer and two non-dough filler materials are described as components. The dough is extruded under pressure and expands upon release from the nozzle surrounding a pair of tubes which place the filling into the center of the tubes. The filling material is supplied to the extruder through separate tubes and there is no discussion in the patent that the nozzle and/or extruder can be used to extrude dough comprising potato shreds.
U.S. Pat. No. 4,259,051 addresses extrusion apparatus for forming a hollow foodstuff of extruded plastic material which can be simultaneously filled. There is no discussion in the patent that the apparatus can be used for potato shred dough, and the apparatus cannot likely be used for extruding a plurality of axial cavities.
U.S. Pat. No. 5,527,179 describes an apparatus for extruding dough in hollow form through the use of a solid pin within the extrusion nozzle. U.S. Pat. No. 4,900,572 describes an apparatus for making dog food where an outer layer is extruded into a chamber having sleeves. An inner layer is extruded through the sleeves and, thus, the inner layer becomes covered by the outer layer. U.S. Pat. No. 5,645,872 describes extrusion of hollow shapes of material subject to coagulation by allowing gas or liquid to flow into the center cavity after extrusion to foster coagulation and avoid collapse of the hollow extruded shape.
U.S. Pat. No. 4,828,856 describes hash brown type potato products made from de-hydrated formed or fabricated potato shreds which can be re-hydrated and formed into patties said to simulate fresh cut potato products. The re-hydrated mass has a moisture content of 40% to 55% so that the product can be sheeted with a 1 to 2 millimeter opening between sheeting rolls. The potato dough made from the shreds described in this patent cannot be extruded because of needed high extrusion pressures which are said to rupture a significant portion of the potato cells. Non-critical ingredients for these products are carboxymethylcellulose, which is said to be a processing aid for the sheeting operation, and certain food gums to reduce fat or oil pickup (uptake) during frying. U.S. Pat. No. 5,492,704 describes a process for making potato strands comprising shreds for use in hash brown potatoes, and re-hydration of the shreds in the form of sheets to make a hash brown potato product is exemplified in the patent.
U.S. Pat. No. 5,891,596 describes potato mixtures shaped by extrusion or otherwise that are processed as a reduced fat flash frozen potato product. The formed potato shapes are made from blended potato pieces, and the blended product contains small pieces and, thus, not potato shreds. U.S. Pat. No. 3,399,062 describes dehydrated granular products, such as crushed dehydrated potatoes, containing some aggregates of individual cells, re-hydrated at low temperature in the presence of cellulose ether thermal gelling agent and extruded to obtain a french fried potato product.
U.S. Pat. No. 3,975,549 describes agglomerated dehydrated potato products made from dehydrated potato particles that, after re-hydration with a binder, are extruded to form french fries. The binder may be either a gum, such as guar gum, or free starch from modifying the potato solids. U.S. Pat. No. 3,987,210 describes an extruded french fried potato product comprising dehydrated potatoes in the form of flakes, granules, flour, diced pieces or mixtures thereof with a binder comprising more than about 25% amylose starch. The starch is said to retrograde when heated with water to form a film around the product and provide an oil barrier.
U.S. Pat. No. 3,486,673 describes extruded french fried potato products comprising dehydrated mashed potatoes, methyl cellulose and polygalacomannan gum, which are said to be essential ingredients. The combination of ingredients reportedly provide the product with an irregular external crust which permits the product to pick up a modest amount oil during frying. U.S. Pat. No. 5,242,699 addresses an application of a hydrocolloid coating to potato strips to provide an exterior crust when the strips are blanched or par-fried which may also retard oil adsorption into the potato strip. U.S. Pat. No. 5,620,727 concerns use of low molecular weight ionic hydrocolloid compositions to make film to reduce oil uptake. U.S. Pat. No. 3,687,688 concerns immersion of potato into a batter comprising sodium alginate for moisture control, and U.S. Pat. No. 4,900,573 concerns batter comprising hydroxypropyl methylcellulose which is said to function as an oil barrier.
Fat absorption/uptake of fried foods is one of the major concerns of consumers, particularly with respect to dietary concerns as fat provides approximately 9 calories per gram to the food. Also, fat leaching from a prepared product during re-heating or reconstituting causes a greasy feel to food, and imparts undesirable organoleptic qualities to the food.
An object of the invention is a multiple extrusion nozzle that can be used in conjunction with commercially available extruders, particularly co-extruders, which can extrude hollow continuous ropes in the form of casings having two or more axial cavities, preferably two or three. It is a further object of the invention to enable extrusion of a product having an outer casing with one or more axial indented ridge type connectors that allows sections of the casing to be broken apart to make pieces which can be consumed individually. A further object of the invention is the filling of the axial cavities simultaneously with extrusion. These, and other objectives of the invention, are achieved by the multiple extrusion nozzle, apparatus and methods described herein.
Other objects of the invention are to make a hand held convenience snack food product that comprises a casing with potato shreds that can be extruded in the multiple extrusion nozzle and filled and then cooked, such as partially or fully fried or baked, without significant excess oil absorption during cooking and without oil or fat leaching during reconstitution and an extrudable casing comprising potato shreds that has structural integrity which can withstand the extrusion and filling process, and other processing to, in certain embodiments, axially join outer walls of two or more casings. These objectives are achieved by the unique potato shred matrix of the casing and the selection of cellulose gums which, with starch, forms a film on the exposed surfaces of the casing filling the voids in the potato shred matrix on exposed surfaces, which strengthens the matrix and inhibits oil/moisture transmission. These objectives are further achieved by the incorporation of axial indented ridge type connectors.
The invention provides for an extruded baked or fried product comprising potato shreds wherein the integrity of the shreds is maintained despite the extrusion process. The cellulose gums and starch form a film around the exposed surfaces of the potato shred casing filling the voids at the exposed surfaces of the casing. As such, the casing maintains its shape during and after extrusion and the film helps control both oil pick-up during cooking and oil or fat leaching when the product is reconstituted. The moisture content is also important to processability as the moisture content of the casing, about 55% to about 75%, preferably about 60% to about 72%, facilitates extrusion and regulates oil uptake during cooking.
In the present Specification, all parts and percentages are by weight/weight unless otherwise specified.